The present invention generally relates to packaging for medical devices, and more particularly to packaging which includes a plurality of discrete retainers for restricting movement of a medical catheter from a desired shape.
Medical catheters of different types are used for a wide variety of purposes and techniques, including electrophysiology, neuroradiology, and coronary angioplasty and angiography. Coronary catheterization is conducted by inserting the tip of a catheter into an incision in the leg or arm of the patient, and then pushing the catheter into and through body passageways such as the lumen of a blood vessel, artery or heart passageway. The desired procedure is then performed at the distal tip of the catheter, such as injecting a radiopaque dye during angiography.
Coronary catheters generally have a proximal hub, a body, and a distal tip portion. The body and tip portion are formed of a long, flexible, tubular material having sufficient length to traverse a path from the incision to the coronary region. The body portion is relatively long and straight, while the tip portion is comparatively short and usually curved. The hub surrounds the proximal end of the catheter, and it has an axial passage and a coupling collar for connecting the catheter with a pressure source or dye reservoir. The hub may also have radially extending wings for enabling a physician to twist the hub and impart torque on the catheter to manipulate the distal tip portion.
The operational requirements of the catheter mandate the selection of a material having adequate characteristics, including flexibility, torque transmission, pushability, and resiliency. Flexibility enables the tubing of the catheter to wind its way through convoluted body passageways, such as through branching blood vessels and curved pathways within and into blood vessels, body cavities, or organs. The catheter should also adequately transfer torque so that the physician can manipulate and steer the distal tip portion by twisting the proximal hub. The catheter must possess sufficient longitudinal or column resistance, referred to as pushability, to negotiate through these passageways. Finally, the catheter must be resilient, tending to recover its prior shape after bending, referred to as shape memory. This being the case, catheters are often made of certain polyurethane materials that are advantageous for many uses, including coronary angiography and angioplasty applications.
Surgeons and medical teams request catheter tip portions having specially designed shapes, so that the catheter can be steered through the correct body passageways, and can perform the desired operation. It is thus important that these shapes be maintained accurately during manufacturing, sterilization, transport, storage, removal and utilization. The curved tip configuration must be maintained, not only during transport and storage, but also when the medical team slides the catheter and its curved tip from the packaging Just prior to a medical procedure. As a result, the packaging must not only protect the catheter, it must also maintain the desired shape of the catheter until the catheter is used.
Accordingly, it is desirable to retain the body of the catheter in as straight a position as possible so that it does not induce any trauma to the body and retains acceptable pushability. However, the tip portion is intentionally curved and must recover to this desired shape after the catheter is removed from the packaging. The catheter is conventionally removed from the packaging by partially peeling the upper web from the lower web in the area near the proximal hub of the catheter, and then longitudinally pulling the catheter from the packaging by grasping the hub. As the catheter is removed, the curved tip portion directly contacts each of the cross-foot serrations sequentially. The packaging should therefore preferably minimize any bending stress on the curved tip portion during placement into, storage within, and removal from the packaging.
An example of previous packaging for a catheter is described in U.S. Pat. No. 5,131,537, filed on Oct. 3, 1991, which is entitled "Flexible Tip Tray Packaging for Medical Catheters", which is commonly assigned and includes a relatively stiff mounting card, an upper web, a lower web, and a flexible tip tray. The upper web has been formed of extruded Mylar.RTM. material, while the lower web has been made of porous Tyvek.RTM. material. The upper and lower webs are peripherally sealed to define a pouch containing the mounting card and catheter. The tip tray is provided for protecting and maintaining the desired curve of the distal tip portion of the catheter during storage. The mounting card has a hub recess hole for partially receiving the hub of the catheter, to reduce damage by the hub to the upper web.
The catheter body portion was retained in a straight position relative to the mounting card by a plurality of cross-foot serrations which contact the catheter body directly. While the cross-foot retainers perform their intended function adequately, it is desirable to provide retainers which restrict movement of the catheter body from a straight position, yet which do not directly contact the catheter or require the card to be cut. In addition, the catheter must presently be placed into the cross-foot serrations manually, so it would be advantageous to provide packaging having a design which can be assembled in an automated process.
It is accordingly a general object of the present invention to provide an improved catheter packaging assembly which restricts movement of the catheter from a desired position without directly contacting the catheter body, and which can be manufactured in an automated process.
An additional object of the present invention is to provide improved retainers for use in packaging for a medical catheter which do not require a mounting card to be perforated.
The unique packaging assembly of the present invention incorporates a plurality of discrete retainer elements which do not directly contact the catheter body, yet restrict its movement from a desired position. The retainer elements of the present invention are preferably formed by simultaneously applying heat and pressure to the cover sheet to partially melt it, thus Joining a portion of the cover sheet to the mounting card without requiring serrations. Moreover, the packaging of the present invention may be assembled by an automated process.
These and various other objects, advantages and features of the invention will become apparent from the following description and claims, when considered in conjunction with the appended drawings.